target/linux/s3c24xx/patches-2.6.26/0189-fix-touchscreen-meddling-divde.patch.patch

   1 From 9bdb2dbc9725d7f2ba23566303d5abe0504beb83 Mon Sep 17 00:00:00 2001
   2 From: Andy Green <andy@openmoko.com>
   3 Date: Fri, 25 Jul 2008 23:06:16 +0100
   4 Subject: [PATCH] fix-touchscreen-meddling-divde.patch
   5  Reported-by: Holger Freyther <zecke@openmoko.org>
   6
   7 length can be zero... blowing a divide by zero exception...
   8 which somehow I don't get (?)  Anyway the code is wrong and
   9 this should fix it.
  10
  11 Signed-off-by: Andy Green <andy@openmoko.com>
  12 ---
  13  drivers/input/touchscreen/s3c2410_ts.c |   12 +++++++++---
  14  1 files changed, 9 insertions(+), 3 deletions(-)
  15
  16 diff --git a/drivers/input/touchscreen/s3c2410_ts.c b/drivers/input/touchscreen/s3c2410_ts.c
  17 index b1ba73d..5bc347f 100644
  18 --- a/drivers/input/touchscreen/s3c2410_ts.c
  19 +++ b/drivers/input/touchscreen/s3c2410_ts.c
  20 @@ -226,12 +226,18 @@ static irqreturn_t stylus_action(int irq, void *dev_id)
  21         unsigned long x;
  22         unsigned long y;
  23         int length = (ts.head_raw_fifo - ts.tail_raw_fifo) & (ts.extent - 1);
  24 -       int scaled_avg_x = ts.raw_running_avg.x / length;
  25 -       int scaled_avg_y = ts.raw_running_avg.y / length;
  26 +       int scaled_avg_x;
  27 +       int scaled_avg_y;
  28
  29         x = readl(base_addr + S3C2410_ADCDAT0) & S3C2410_ADCDAT0_XPDATA_MASK;
  30         y = readl(base_addr + S3C2410_ADCDAT1) & S3C2410_ADCDAT1_YPDATA_MASK;
  31
  32 +       if (!length)
  33 +               goto store_sample;
  34 +
  35 +       scaled_avg_x = ts.raw_running_avg.x / length;
  36 +       scaled_avg_y = ts.raw_running_avg.y / length;
  37 +
  38         /* we appear to accept every sample into both the running average FIFO
  39          * and the summing average.  BUT, if the last sample crossed a
  40          * machine-set threshold, each time we do a beauty contest
  41 @@ -280,7 +286,7 @@ static irqreturn_t stylus_action(int irq, void *dev_id)
  42         else
  43                 ts.flag_previous_exceeded_threshold = 1;
  44
  45 -       /* accepted */
  46 +store_sample:
  47         ts.xp += x;
  48         ts.yp += y;
  49         ts.count++;
  50 --
  51 1.5.6.3
  52